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Magnetostatic Wave and Magnetostatic Wave-Optic Filter Technology(*) Introduction This article discusses applications of magnetostatic waves (MSW) in epitaxial magnetic garnet films for the design and fabrication of bandpass filters. Three [...]

Single crystals of lead bromide doped with silver bromide were grown by the vertical Bridgman method. Direct observations were made in order to understand the interfacial instabilities. Numerical studies were carried out to provide a framework for interpreting the observed convective and morphological instabilities. Observations on interfacial instabilities in lead bromide with 500 and 5000 ppm silver bromide impurities supported the numerical results predicted for 1-g conditions. X-ray rocking curves, X-ray contour scans, and etch-pit studies showed that increasing solutal convection deteriorated the crystal quality of the crystals.

Resonances due to magnetostatic surface waves propagating around a y.i.g. slab bounded on one surface by a conductor have been observed experimentally and identified with mode numbers. A nonreciprocal transmission band due to the wave propagating along the y.i.g.-metal interface was also observed.

The time delay of magnetostatic surface waves is studied experimentally and theoretically, and the effect of chemical polishing on the attenuation of the waves investigated.

The letter describes experiments performed on magnetostatic-wave propagation, in a transversely magnetised single-crystal plate of yttrium iron garnet at 3.9 GHz. Both surface-and volume-mode resonances were observed and are identified with theory.

Experiments on parametric pumping of an L band 2-port magnetoelastic delay line are described. Two modes of operation were observed; namely, idler generation in an essentially 1-port re´gime and direct amplification of 2-port echoes.

The application is described of magnetostatic wave delay lines to group-delay equalisation at intermediate frequencies of millimetric circular-waveguide lengths utilised in high-data-rate digital communication systems. Experimental results and theory have shown that suitable bias-field-adjustable-delay/frequency characteristics can be realised using surface-wave propagation in thick yttrium-iron garnet (y.i.g.) films grown by liquid-phase epitaxy.

Mixing of oppositely directed magnetostatic waves has been demonstrated in an axially magnetised y.i.g. rod. Using both single and double pulses, convolution has been achieved at 1275 MHz. Measurements and preliminary theory indicate a substantially greater bilinearity factor than that obtainable with devices currently available.

Films of yttrium–iron garnet have been grown on gadolinium-gallium-garnet substrates by liquid-phase epitaxy with thickness up to 100 μm. Measurements by the bandstop-filter technique in the frequency range 2–8 GHz have shown resonance line-widths as low as 20 A/m(0.25 Oe). These results are compared with measurements of linewidth by the cavity-resonance technique at 9.5 GHz.